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Nunes M.C.M.,UNEMAT | Cassol E.A.,Federal University of Rio Grande do Sul
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2011

The sediment particle size distribution depends on soil type and texture. This study had the objective to evaluate the sediment yield by interrill soil erosion in three Oxisols of Rio Grande do Sul state, Brazil: Rhodic Hapludox (LVaf and LVdf) and a Typic Hapludox (LVd), of different textural classes, by simulated rainfall events in laboratory. Experimental plot with test area of 0.36 m 2 and 0.09 m m-1 slope was used. Simulated rainfall with mean intensity of 88 mm h -1 and duration of 90 min was applied in three replications on three oxisols. Sediment particles leaving the experimental plots were collected in a set of sieves. The distribution of sediment diameter varied as the soil texture. The sediment yielded by interrill soil erosion had individual particles and aggregates smaller than those in the original soil. Most of the sediment yielded by interrill soil erosion at LVdf soil was in the class diameter from 9.51 to 4.76 mm whereas in LVaf was from 4.76 to 2.00 mm and in LVd was from 1.00 to 0.25 mm. The original LVdf and LVaf soils present higher clay, organic carbon and iron oxides contents and greater aggregate water stability than the LVd soil, and this probably explains the differences among size classes of sediment yielded by interrill soil erosion.

Roboredo D.,Mato Grosso State University | Maia J.C.S.,UFMT | de Oliveira O.J.,Federal University of Minas Gerais | Roque C.G.,UNEMAT
Engenharia Agricola | Year: 2010

Soil compaction is a problem that interferes in root growth and crop production. This study was conducted in the experimental station of Centro Federal de Educação Tecnológica of Cuiabá (CEFET), in Santo Antonio do Leverger - MT, Brazil. The aim was to evaluate the cone index of the Distrophic Red Latosol in function of different water levels in two depths, by using a constant speed penetrometer and an impact one, correlating them with the soil density. The design was made of randomized blocks with eight treatments and five replications, arranged by split plots, with four bands of soil water content in the plots: range 1 (0.1883 to 0.2354 m3 m-3); range 2 (0.2355 to 0.2544 m3 m-3); range 3 (0.2545 to 0.2702 m3 m-3) and range 4 (0.2703 to 0.3177 m3 m-3), and two depths of sampling like subplots (0.05 to 0.10 m and 0.15 to 0.20 m). From the results it was found that: i) the penetrometers showed significant positive correlation with the soil density; ii) the impact penetrometer presented the highest soil strength.

de Lalla J.G.,Sao Paulo State University | Laura V.A.,Embrapa Gado de Corte | Junior S.S.,UNEMAT | Cardoso A.I.I.,Sao Paulo State University
Horticultura Brasileira | Year: 2010

The objective of this work was to estimate general (GCA) and specific combining ability (SCA) and heterosis of lines and populations of Japanese cucumber using a topcross. We obtained 16 experimental hybrids crossing two test populations (Yoshinari, TY, and Natsusuzumi, TN, F2 population) and eight S5 lines obtained from Hokuho commercial hybrid. The Hokuho hybrid F1 was also evaluated, totalizing 27 treatments. The experimental design used was randomized block, with four replicates and four plants per plot. Weight of total and commercial fruits, total number of fruits, number of commercial fruits, percentage of commercial fruits and average weight of commercial fruits were evaluated. Yoshinari population (TY) presented, on average, better combining ability with lines of Hokuho. Line L7 presented the highest positive values of GCA for most of evaluated characteristics. Hybrids H1Y and H1N, with line L1 as one parental, showed higher values for SCA with the test populations for most of evaluated characteristics, while the hybrids with line L5 (H5Y and H5N) showed the smallest values. Population Yoshinari F2 showed greater potential to obtain lines for crossings with lines of Hokuho, in order to obtain hybrid with high yielding potential. Heterosis was positive for most evaluated characteristics.

This paper describes the identification and quantification of land use changes in the Córrego do Bezerro Vermelho basin, Tangará da Serra, MT, using Landsat images from 1984 and 2011. Images were geo-referenced, classified, and processed by Spring software, and thematic classes were edited and quantified using ArcGis software. The Anthropic Transformation Index was applied to determine the degree of anthropization of the creek. Five classes were identified: forest cover, secondary vegetation, agriculture, pasture, and water bodies. The results indicated a decrease in the class percentiles: 35.35% of forest cover; 11,78% of pastures; and 100% of secondary vegetation, all related to a 248.75% increase in agriculture. The findings of this study indicated that the landscape was drastically altered due to an increase in the Anthropic Transformation Index from 4,75 to 5.88 between 1984 and 2011. Thus, the creek, which that was classified as a regular class in 1984, passed to a degraded class in 2011, due to anthropogenic activities associated with agricultural expansion.

Geron L.J.V.,Mato Grosso State University | Mexia A.A.,Mato Grosso State University | Garcia J.,Mato Grosso State University | Da Silva M.M.,UNEMAT | Zeoula L.M.,State University of Maringa
Semina:Ciencias Agrarias | Year: 2012

The objective was evaluate the levels of concentrate supplementation (0.0%, 0.5%, 1.0% and 1.5% of body weight - BW) consisting of cottonseed with ground corn (CSGC) in proportion 50% each in lambs finished on pasture (Grass Marandu) slaughtered at 31.7 kg BW, on average daily gain (ADG), days of supplementation (DS) and cost of production in the dry season. We used 20 lambs with initial BW 19 ± 0.5 kg in four treatments. CSGC supplementation was provided in stalls separated by level of supplementation the eighteen hours daily. We used a completely randomized design to determine ADG and DS lambs supplemented with different levels of CSGC. The data of ADG and DS were evaluated by regression analysis considering 5% significance. The different levels of supplementation CSGC influenced quadratic (p < 0.05) ADG and DS lambs on pasture. The level of supplementation CSGC to 1.0% BW in lambs finished at pasture in the dry season had the best value of total lucre for the warm carcass of U$ 9,585.00. It was observed that the level of 0.0% BW of concentrate supplementation had the lesser total expenditure amounting to U$ 7,317.82 in relation to other levels of supplementation. It was found that best value of net revenue per month the of U$ 419.75 was obtained for lambs finished on pasture supplemented with a level of 1.0% BW of concentrate containing CSGC. Thus, conclude that lambs finished at pasture can be supplemented with the level of 1.0% BW of CSGC which improves ADG, reduces the DS beyond present the lucre best net/month for this activity.

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